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This question is about gravitational waves postulated by Einstein.

  1. Is gravitational radiation a form of mass/energy that can form momentum?

  2. If it causes ripples in space-time, would space-time be susceptible to forming vortices if massive bodies passed each other at close distances and relativistic speeds?

Sean Carroll raised this possibility, but dismissed it because it was discredited in 2-dimensional space by Gerard 't Hooft.

  1. Has anyone investigated if 3-dimensional space would support space-time vortices, and whether such vortices might cause light cones to tilt as if they were caught in a whirlpool, with a tendency toward a timelike loop?

(R.A. Fessenden speculated about gravity waves and vortices in 1913, but he assumed an ether: http://archive.org/stream/jstor-1638835/1638835_djvu.txt.)

I apologize if this question is naive and too wide-ranging.

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  • $\begingroup$ You seem to have a lot of different questions meshed together. For example, frame dragging in Kerr is a very close analogy of the "space-time vortices" that you are looking for but it's not due to gravitational waves. Are you specifically asked about some kind of frame dragging effect associated with gravitational waves? And yes they can carry momentum and angular momentum. $\endgroup$ – FenderLesPaul Jun 8 '15 at 3:08
  • $\begingroup$ If you are thinking about a vortex in form of a soliton, then I think the answer is "we don't know". It seems that it's not clear, as of now, if stable, mass-free gravitational solitons can exist according to GR. However, GR may not be the correct theory to begin with and if Einstein-Cartan is better, than it's a whole different ballgame, anyway. $\endgroup$ – CuriousOne Jun 8 '15 at 5:04
  • $\begingroup$ @FenderLesPaul: Yes, frame dragging associated with gravitational waves, and whether such a vortex could persist after the passage of a massive spinning object. Thanks for your comment, which helps provide direction for me. $\endgroup$ – Ernie Jun 8 '15 at 17:19
  • $\begingroup$ I don't know if you can get the "space-time vortices" using gravitational waves that you would using Kerr, someone else will have to answer that, but it is certainly true that gravitational waves carrying angular momentum can induce a spin memory effect due to frame dragging and the Sagnac effect. C.f. arxiv.org/pdf/1502.06120v1.pdf $\endgroup$ – FenderLesPaul Jun 8 '15 at 17:29
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Is gravitational radiation a form of mass/energy that can form momentum?

We think so. We haven't detected any gravitational waves as yet, but there's a high degree of confidence that gravitational waves are real.

If it causes ripples in space-time, would space-time be susceptible to forming vortices if massive bodies passed each other at close distances and relativistic speeds?

Again, we think so. But like Fender said, that's to do with gravitomagnetism rather than gravitational waves. See this NASA article:

enter image description here

It starts with this: "Einstein was right again. There is a space-time vortex around Earth, and its shape precisely matches the predictions of Einstein's theory of gravity. "

Has anyone investigated if 3-dimensional space would support space-time vortices

Yes, see above.

and whether such vortices might cause light cones to tilt as if they were caught in a whirlpool, with a tendency toward a timelike loop?

No. I'm sorry, but while the vortices are bona-fide physics, time machines are mere science fiction. Maxwell talked about vortices.

(R.A. Fessenden speculated about gravity waves and vortices in 1913, but he assumed an ether: https://archive.org/stream/jstor-1638835/1638835_djvu.txt.)

Don't worry about ether. See this and see arXiv for papers with aether in the title. The people who say it's discredited and a dirty word are usually media hacks and celebrity quacks who don't know about GR or Einstein's Leyden Address. That's where he described space as the aether of general relativity.

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  • $\begingroup$ We have detected energy and angular momentum loss which can be explained with gravitational waves, though , which strongly constrains the question of whether they exist and what properties they have. $\endgroup$ – CuriousOne Jun 8 '15 at 8:50
  • $\begingroup$ @CuriousOne : no problem, see PSR B1913+16. IMHO most people are happy that a wave is a field-variation, and if you can have a field you can have a field variation. Interestingly, Einstein talked about an aether, but the Michelson-Morley experiment couldn't detect one. And like the Michelson Morley experiment, LIGO is an interferometer! $\endgroup$ – John Duffield Jun 8 '15 at 12:24
  • $\begingroup$ Your first response might need updating... $\endgroup$ – Kyle Kanos Feb 15 '16 at 12:49

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